Heinrich F.E. Lenz (1804-1865), born in the old university city of Tartu, Estonia (then in Russia), was a professor at the University of St. Petersburg who carried out many experiments following the initiatives of Faraday. He is memorialized by the law which bears his name - the electrodynamic action of an induced current equally opposes the machanical inducing action- which was later recognized to be an expression of the conservation of energy. His early life is not documented but it is thought that he originally studied for the priesthood.